Objectives: To elucidate the normal and abnormal structure of elastin and collagen and their associated cellular and intercellular components. Major findings: 1. In collaboration with Dr. Hough and Dr. Sokoloff the scanning electron microscope was used as an electron probe for the energy dispersive x-ray analysis of the tide mark and osteochondral junction and adjacent cartilage and bone from the articular regions of joints; human and animal. The tide mark, in decalcified sections, had an excess of calcium but not of sulfur or phosphorus. The calcium excess may explain its hematoxylinophilia. The osteochondral junction does not seem to be hypercalcified as reported in the literature. 2. Also, in collaboration with Hough and Sokoloff we have done an EDAX (energy dispersive analysis by x-rays) study of cartilage in hemophilic anthropathy using the scanning electron microscope as an electron probe. Abnormal inclusions containing iron associated with phosphorus are present withing the chondrocytes in advanced hemophilic anthropathy. Proposed course; 1. Apply the scanning electron microscope with the energy dispersive x-ray analyzer to the analysis of connective tissues, particularly elastin and elastotic degeneration (senile elastosis). 2. With Dr. Hough prepare an article "X-ray Analysis of Mammalian Joints" for a Hayet Monograph.